Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P. R. China.
Anal Chem. 2023 Aug 29;95(34):12768-12775. doi: 10.1021/acs.analchem.3c01477. Epub 2023 Aug 16.
Herein, a surface-enhanced Raman scattering (SERS) biosensor was constructed by gold nanobipyramid (Au NBP) hotspot aggregation-induced SERS (HAI-SERS) for the ultrasensitive detection of microRNA-221 (miRNA-221). Impressively, compared with single Au NBP, the multiple Au NBPs assembled by tetrahedral DNA nanostructures (TDNs) could increase hotspot aggregation to significantly enhance the SERS signal of Raman molecule methylene blue (MB). Meanwhile, in the aid of Exo-III assisted target cycle amplification and TDNs-induced catalytic hairpin assembly (CHA) amplification, the biosensor could achieve the sensitive detection of miRNA-221 with a linear range of 1 fM-10 nM, and the limit of detection (LOD) was 0.59 fM, which could be used for practical application in MHCC-97L and MCF-7 cell lysates. This work provided a method for hotspot aggregation to enhance SERS for the detection of biomarkers and disease diagnosis.
本文构建了一种基于金纳米双三角体（Au NBP）热点聚集诱导表面增强拉曼散射（HAI-SERS）的表面增强拉曼散射（SERS）生物传感器，用于超灵敏检测 microRNA-221（miRNA-221）。令人印象深刻的是，与单个 Au NBP 相比，由四面体 DNA 纳米结构（TDN）组装的多个 Au NBPs 可以增加热点聚集，从而显著增强拉曼分子亚甲基蓝（MB）的 SERS 信号。同时，在外切酶 III 辅助目标循环扩增和 TDN 诱导的发夹组装（CHA）扩增的辅助下，该生物传感器能够实现 miRNA-221 的灵敏检测，线性范围为 1 fM-10 nM，检测限（LOD）低至 0.59 fM，可用于 MHCC-97L 和 MCF-7 细胞裂解物的实际应用。这项工作为热点聚集增强 SERS 用于生物标志物检测和疾病诊断提供了一种方法。
